TV Tomorrow: ATSC 3.0 Advances

WASHINGTON—In the future, broadcast TV signals around the world will accommodate 4KTV, immersive audio, interactivity, multiscreen viewing, mobile devices and hybrid services. This is the underlying goal of ATSC 3.0, the TV transmission methodology now in development at the Advanced Television Systems Committee, a consortium of broadcasters, vendors and trade groups involved in standards development.

The ATSC announced that 10 proposals have been submitted for the foundation of 3.0 known as the “physical layer.” This physical layer includes the modulation scheme, which defines how the signal information is carried by a radio frequency—in this case, the TV channel.

ATSC 3.0 will be a radical departure from the current standard. ATSC 1.0 was developed around 20 years ago, when cellphones were analog and streaming was unheard of. It relies 8-VSB modulation capable of delivering 19.39 Mbps in a 6 MHz TV channel—enough to carry a high-definition program compressed by a factor of 50 using MPEG-2 to a fixed receiver.

ATSC 2.0 Status Report
The simultaneous development of dual broadcast transmission standards reflects how rapidly the technology is evolving. The current standard, ATSC 1.0, was implemented before texting and didn’t anticipate transmission to mobile devices. ATSC 2.0 will enable over-the-air video-on-demand, online interactivity, push alerts to sleeping TVs, and the ability to watch two channels simultaneously on a single screen, among other functions. It will also continue to support the type of linear service now enabled by ATSC 1.0.

ATSC 2.0 was initially on track for completion by mid-2012, but delays ensued. While it has not yet gone to ballot as a candidate standard a source familiar with its development says “the pieces are falling into place fairly rapidly now—standardization in the fall is not an unreasonable target.”

The source said adopting ATSC 2.0 is a “fairly low bar” for broadcasters and TV manufacturers. “" Authoring tools need to be developed for broadcasters, but are not particularly daunting in terms of complexity and cost, and many of the needed changes in TV sets are software-based, at least for smart TVs that are by definition Internet-enabled, so manufacturers won’t have to deal with large bill of material increases in the sets.”

With ATSC 3.0, the committee seeks to increase that data rate by 30 percent, or roughly 25.2 Mbps. The overall intent of 3.0 is to enable seamless transmission of HD, 4K, 22.2 audio and other data streams to fixed, mobile and handheld devices in all types of terrain.

The functional requirements set forth for ATSC 3.0 support that goal by emphasizing flexibility and scalability, e.g., adaptive and variable bit rates, various Quality-of-Service methodologies, independent data pipes, multiple concurrent service support and bandwidth agility.

The “physical layer shall support configurations for differing coverage scenarios, topographies and morphologies,” the 3.0 Physical Layer Call for Proposals states. “Seamless changes to robustness and data rate of portions of streams shall be enabled.”

Support for single-frequency networks, such as those used in distributed transmission systems, is included by way of tolerance for “long man-made echoes.” Distributed transmission systems are favored for mountainous areas because they use synchronized multiple terrestrial transmitters rather than one large one that can leave coverage gaps.

The most differentiating characteristic of ATSC 3.0 is that it will not be backward-compatible with 1.0 or even 2.0, which is now in development. In other words, televisions now capable of processing over-the-air TV signals will not be able to decode ATSC 3.0 signals. It is also being developed with a global perspective in mind, meaning that modulation schemes other than 8-VSB—particularly co-orthogonal frequency-division multiplexing, or COFDM—will likely be on the table.

One further complication is the continued poaching of broadcast spectrum by the wireless industry. Broadcasters lost nearly a quarter of their spectrum to wireless providers in the 2009 digital transition, and face the potential of losing 40 percent of what remains in next year’s incentive auction. Broadcaster participation in the 2014 auction is voluntary, but there’s been no discussion of what happens if too few participate to cover the cost of the auction.

Despite these uncertainties, there is general consensus among broadcasters that their infrastructure needs a futuristic overhaul. Hence the development of ATSC 3.0. Establishing the physical layer was the first step. The subcommittee assigned to hammer out ATSC 3.0—TG3—was formed two years ago and is chaired by James Kutzner of PBS. Luke Fay of Sony and Bill Hayes of Iowa Public TV serve as vice chairmen of the Specialist Group on the Physical Layer for ATSC 3.0. The group issued a Call for Proposals in late March. Initial submissions were due Aug. 23. A total of 19 organizations submitted 10 proposals:

  • Coherent Logix and Sinclair Broadcast Group
  • Communications Research Centre and Electronics & Telecommunications Research Institute
  • Digital Video Broadcasting Project
  • LG Electronics, Zenith and Harris Broadcast
  • Allen Limberg
  • National Engineering Research Center of Digital Television, Shanghai Jiao Tong University, Shanghai Advance Research Institute, and Bell Labs, Alcatel-Lucent
  • Power Broadcasting
  • Qualcomm and Ericsson
  • Samsung and Sony
  • Technicolor

Finalized printed documents are due Sept. 27, 2013. The goal is to produce a candidate standard by 2016.

March 28, 2013,
ATSC Seeks Next-Gen TV Physical Layer Proposals
It appears some of the requirements could be a bit of a stretch, but that may not be such a bad idea, considering that ATSC 3.0 will be replacing a terrestrial DTV standard that’s survived for 15 years.

February 22, 2013,HPA 2013: ATSC 3.0 Update
The current standard was developed 20 years ago and implemented around 15 years ago. The Internet was on baby legs, processor speeds were measured in megahertz, storage in megabytes, and networks in kilobytes.

January 22, 2013,New ATSC Implementation Teams to Focus on Commercialization of ATSC 2.0 and M-EAS
The Advanced Television Systems Committee has formed new Implementation Teams for two new emerging standards -- ATSC 2.0 and the Mobile Emergency Alert System.

February 15, 2012,HPA Tech Retreat: The State of ATSC 2.0
ATSC 2.0 will provide a variety of interactive capabilities to broadcasters not now available.

September 6, 2011,New ATSC 3.0 Technology Group Formed To Anticipate TV of the Future
ATSC 3.0 is anticipated to be a series of voluntary technical standards and recommended practices for the next digital terrestrial television broadcast system.